Is my mobo dead?

Hi All Thanks for reading my thread trying to fix a friends computer Asus P5 LMX mobo 2.8 ghz cpu 1gig ram running XP.
Doing all sorts of weird things originally started blue screening or just doing random reboots to him so on my first inspection i found the power supply fan wasn't working causing the psu to over heat (codgen 350w yuck ) thought would be an easy fix but after replacing that turn the thing on two or three times with no display (onboard video ) then the fourth time with a continuos beeping then the fifth time comes up with ucode loading error overclocking failed or voltage error but the system has never been overclocked ,thought i would replace the ram but to no avail now the system has gone into a continuos loop even changed hard drive reset the bios to factory default every now and then it starts up windows but eventually just reboots Mobo Dead?or Dying hope i have given enough info and posted in the right spot
Cheers Herb